How does phenytoin work?
Phenytoin stabilises nerve signals in the brain, preventing them from becoming overactive and causing seizures.
What is phenytoin used to treat?
Phenytoin is commonly prescribed for:
- Epilepsy (to prevent and control seizures)
- Status epilepticus (a medical emergency involving prolonged seizures)
- Seizures caused by brain injury or surgery
Who can take phenytoin?
Phenytoin is suitable for most adults and children, as prescribed by a doctor.
Who might not be able to take phenytoin?
Phenytoin may not be suitable if you:
- Have liver disease
- Have a history of heart rhythm problems
- Have a history of allergic reactions to antiepileptic drugs
- Are taking other medications that interact with phenytoin
Can I take phenytoin if I’m pregnant or breastfeeding?
Phenytoin isn’t usually recommended during pregnancy, as it may increase the risk of birth defects. If you’re breastfeeding, consult your doctor before use.
What if I miss a dose?
If you forget a dose, take it as soon as you remember. If it’s close to your next dose, skip the missed one—do not take two doses at once.
How effective is phenytoin?
Phenytoin is highly effective at preventing seizures when taken consistently as prescribed.
What should I do if I take too much?
Taking too much phenytoin can cause confusion, dizziness, slurred speech, or loss of coordination. If you think you’ve taken too much, seek emergency medical help immediately.
What dose of phenytoin is usually taken?
- For epilepsy: 200mg to 500mg daily, divided into smaller doses
- For status epilepticus: Given as an injection in hospital
Your doctor will determine the correct dose based on your condition.
Powered by pharmacies
With over 1,700 pharmacy partners across the UK, you can get the help you need, wherever you are based.
Our website and mobile app make it easy and convenient to manage your health needs and book services at a pharmacy nearby.
What are the side effects of phenytoin?
Common side effects include:
- Dizziness or drowsiness
- Gum swelling or bleeding
- Nausea or stomach pain
- Changes in coordination or balance
Serious side effects, such as irregular heartbeats, severe skin reactions, or mood changes, require urgent medical attention.
How should I take phenytoin?
Phenytoin is taken as capsules, tablets, or liquid, usually once or twice daily.
When should phenytoin be taken?
Phenytoin should be taken at the same time each day, with or without food.
What are the brand names for phenytoin?
Phenytoin is available as a generic medicine, but some branded versions include:
- Epanutin
Final thoughts
Phenytoin is an effective medication for preventing seizures, but it should be taken exactly as prescribed. Regular blood tests may be required to monitor drug levels. If side effects occur, speak to your doctor or pharmacist.
